This invention relates generally to surgical instruments and methodology, and relates more specifically to instruments specifically adapted for microsurgical medical procedures.
It is estimated that in the United States today, over 30,000 operations involving microsurgical techniques are performed annually. The techniques of microsurgery largely evolved in the areas of vascular and neurosurgery, and are used in bypass and brain tumor procedures. However, as the techniques have become established and better known, applications in other fields have appeared, and they are now common in opthamalogic surgery, reattachment of digits and limbs, in vasovasotomy procedures and in other surgical areas. In one reported study, non-microsurgical vasovasotomy (the repair of a vasectomy) had a success rate as measured by the presence of motile sperm in the ejaculate of only 5%. Dr. Marc Goldstein, Director of the Cornell Medical Center Urologic Microsurgery Unit, however, reported over 90% success using microsurgery.
Understanding of the present invention will be facilitated by a consideration of the conditions under which such procedures are carried out.
First, the tissues, vasculature or other area subject to the procedure are so minute that a binocular microscope is used, the magnification being typically in the range of 6 to 40 power. Generally speaking, individual tools used in these procedures are miniaturized versions of tools used in standard surgery. Unlike standard, gross-field surgical techniques, in which suture material ranges from stainless steel wire up to 24 gauge to 6-0 material and can be threaded or swaged to needles of significantly larger diameter, microsurgery requires the use of suture material directly swaged to needles from 50-100 microns in diameter and the suture itself is in the range of 8-0 (0.04 mm to 0.049 mm) to 11-0 (0.019 mm) in diameter.
Sure-handedness is the hallmark of the microsurgeon. In procedures that may last as long as ten hours, fatigue, eyestrain and irritation are factors which may impair a microsurgeon's ability to perform, and must be taken into account. Any means that will speed up a procedure is desirable, as is any means that will make the surgeon more comfortable as he or she carries out this exacting craft. More particularly, there is a natural tendency for the hands to move from their original orientation when a surgeon is not observing the position of the hands. The ability to maintain direct and continuous eye contact on hand position helps prevent accidental injury to tissue by inadvertent hand movement.
In order to better appreciate the severity of the aforementioned difficulty, it is important to understand that the type of binocular viewing system which is used by the surgeon during microsurgery techniques, bears but limited resemblance to the conventional device used in the laboratory, wherein specimens being observed are directly aligned with the viewer's axis of sight. In this conventional arrangement, the viewer thus looks through the binocular microscope at a sample which is positioned directly beneath and aligned with the longitudinal axis of the microscope. Accordingly, it is a relatively simple matter for the surgeon to remove or deflect his or her vision momentarily from the microscope to observe without the aid of same. Correlation of hand movements is simple in this instance too, in that the only effect actually achieved by the microscope is to amplify the field of vision, which in a sense is directly in front of the viewer to begin with.
However, in the instance of the type of sophisticated instrumentation used in microsurgery for viewing the area in which operations are being carried out, much more complex systems are involved, which are usually referred to as "surgical operating microscopes". Instruments of this type are available from several sources, including Carl Zeiss, Inc. of Thornwood, N.Y., and Wild Heerbrugg, Ltd., of Heerbrugg, Switzerland. In these highly sophisticated instruments, the binocular eyepieces are arranged at an angle up to 90.degree. with respect to the objective lenses (indeed, several such binocular viewing ports may form part of a single operating microscope, so that several surgeons and/or assistants can view the operating field at one time). This arrangement is intentional in that it enables the surgeon to conduct procedures while standing in an upright position, or in a slightly leaning over position while the hands of the surgeon carry out the procedures in the operating zone. Thus, the surgeon, while looking through the binocular instrument and gazing upon the field of operation, is not in a position wherein the line of eyesight normally physically intersects the operating zone. The effect is as if the zone being viewed were not directly connected with the normal physical arrangement of viewing, and this in part accounts for the aforementioned difficulties of reorienting the instruments and hands to the operating zone in the event the surgeon physically removes his or her eyes from the microscope to observe other areas of the operating room, to grasp instruments from an attendant, or from a side platform, or so forth.
Pursuant to the foregoing, it would therefore be exceedingly desirable were the surgeon able to maintain his or her position at the viewing port of the binocular microscope as a change is made from one to another of the instruments, which may be sequentially utilized in the course of an operation. However, this has not heretofore been possible in that normal procedure has required to the contrary, that when instruments are sequentially utilized, the surgeon must change from a first to a second instrument, often necessitating removal of the surgeon's gaze from the operating field as aforementioned, with attendant loss of time and precision, and with the generation of fatigue and irritation.
While it has heretofore been known to provide double-ended surgical instruments, these full size instruments of the prior art have little or nothing to do with the problem to which the present invention is addressed. Thus, for example, the 1980 American Hospital Supply Corporation, American v Mueller Division catalogue, entitled "Surgical Armamentarium" illustrates at pages 369, 554 and 749 such double-ended instruments of the prior art. These instruments will be found to essentially constitute arrangements of like tools at each end of a single handle. There is no provision for interchangeability of the respective ends, and more significant, there is no relationship between the opposed ends of these tools, which is a criteria which is totally essential for use in a microsurgical instrument in order to meet the objectives of this invention.
Pursuant to the foregoing, it may be regarded as an object of the present invention, to provide a bipolar microsurgical instrument which enables a surgeon user thereof to effect successive operative steps incident to microsurgical procedures, while retaining the surgeon's position at a microscopic viewing port defining a field of vision wherein the instrument is being used to effect such procedures.
It is a further object of the invention, to provide an instrument as aforementioned, having interchangeability aspects with respect to the tools on the bipolar instrument; and wherein the interchangeable features are specifically related to the sequential use of the instruments thus joined.
It is yet a further object of the invention, to provide a kit for assembling therefrom a determinatively configured bipolar surgical instrument, which enables the user to effect successive operative steps incident to microsurgical procedures while retaining the surgeon's position at a binocular microscopic viewing port as aforementioned.